RBD Angular Spring Constraint dynamics node

Constrains an RBD object to have a certain orientation, but with a set amount of springiness.

On this page

Using RBD Angular Spring Constraints
Parameters
Inputs
Outputs
Locals
Examples

This involves constraining the orientation of the RBD Object to a “goal” orientation derived from another simulation object or from an orientation in world space.

RBD Angular Spring Constraint is a digital asset.

Using RBD Angular Spring Constraints ¶

Click the RBD Angular Spring Constraint tool on the Rigid Bodies tab.
Select the object to constrain and press Enter to confirm your selection.
Select the position for the angular spring constraint and press Enter to confirm your selection.

Note

You can hold Alt to detach the constraint from the construction plane.
Set the Strength and Dampening on the Spring tab in the parameter editor.

Note

To parent to another object, use the Parent Constraint tool.

Parameters ¶

Constraint ¶

Constrained Object

Identifies the RBD object to be constrained.

Goal Object

Identifies an RBD object used to determine the goal orientation. If this parameter is left blank then the objects will be constrained to a world space orientation.

Constrained Location

Specifies a position in world space used to initialize the local object space position of the constraint.

Goal Location

Specifies a location in world space used to initialize the goal position for the constraint.

Goal Rotation

Specifies a rotation in world space used to initialize the goal rotation for the constraint.

Mirror Constraint

If enabled, all objects involved in the constraint will be made mutual affectors.

Spring ¶

Strength

Controls how strongly the spring constraint acts on the constrained object to return the anchors to the same orientation.

Damping

Controls the amount of damping in the spring relationship. As damping increases, the spring constraint acts more slowly and oscillates less.

Rest Rotation

Sets the rest angle between the object and goal. The force applied on a constrained object by a solver will tend to keep the object rotated by this amount relative to the goal object.

Limit Torque

If this is set, the constraint will be disabled if the torque applied to satisfy this constraint exceeds the maximum specified by the “Maximum Torque” parameter.

Maximum Torque

Sets a threshold for disabling the constraint. If the torque applied to satisfy this constraint exceeds this threshold, the constraint will be disabled.

Limit Rotation

If this is set, the constraint will be disabled if the angle between the two constrained objects exceeds the maximum specified by the “Maximum Rotation” parameter.

Maximum Rotation

Sets a threshold for disabling the constraint. If the angle between the two constrained objects exceeds this threshold, the constraint will be disabled.

Bullet Data ¶

The following parameters are used by the Bullet Solver.

Constraint Iterations

If greater than zero, overrides the number of iterations performed by the constraint solver for this constraint. If some groups of constraints require more iterations than others, this parameter can be used instead of globally increasing the number of iterations on the solver.

Disable Collisions

Disables collision detection between the constrained pair of objects.

Guide Options ¶

Show Guide Geometry

Turning on this option causes guide geometry to be displayed in the viewport representing this constraint.

Radius

Controls the radius of the spheres drawn in the viewport as guide geometry for this constraint.

Color

This parameter controls the color of the guide geometry.

Show Object Link

This parameter controls the display of guide geometry connecting the constraint to the constrained object.

Activation

Determines if this node should do anything on a given timestep and for a particular object. If this parameter is an expression, it is evaluated for each object (even if data sharing is turned on).

If it evaluates to a non-zero value, then the data is attached to that object. If it evaluates to zero, no data is attached, and data previously attached by this node is removed.

Inputs ¶

First Input

This optional input can be used to control which simulation objects are modified by this node. Any objects connected through this input and which match the Group parameter field will be modified.

If this input is not connected, this node can be used in conjunction with an Apply Data node, or can be used as an input to another data node.

All Other Inputs

If this node has more input connectors, other data nodes can be attached to act as modifiers for the data created by this node.

The specific types of subdata that are meaningful vary from node to node. Click MMB an input connector to see a list of available data nodes that can be meaningfully attached.

Outputs ¶

First Output

The operation of this output depends on what inputs are connected to this node. If an object stream is input to this node, the output is also an object stream containing the same objects as the input (but with the data from this node attached).

If no object stream is connected to this node, the output is a data output. This data output can be connected to an Apply Data DOP, or connected directly to a data input of another data node, to attach the data from this node to an object or another piece of data.

Locals ¶

The simulation time for which the node is being evaluated.

Depending on the settings of the DOP Network Offset Time and Scale Time parameters, this value may not be equal to the current Houdini time represented by the variable T.

ST is guaranteed to have a value of zero at the start of a simulation, so when testing for the first timestep of a simulation, it is best to use a test like $ST == 0, rather than $T == 0 or $FF == 1.

The simulation frame (or more accurately, the simulation time step number) for which the node is being evaluated.

Depending on the settings of the DOP Network parameters, this value may not be equal to the current Houdini frame number represented by the variable F. Instead, it is equal to the simulation time (ST) divided by the simulation timestep size (TIMESTEP).

TIMESTEP

The size of a simulation timestep. This value is useful for scaling values that are expressed in units per second, but are applied on each timestep.

SFPS

The inverse of the TIMESTEP value. It is the number of timesteps per second of simulation time.

SNOBJ

The number of objects in the simulation. For nodes that create objects such as the Empty Object DOP, SNOBJ increases for each object that is evaluated.

A good way to guarantee unique object names is to use an expression like object_$SNOBJ.

NOBJ

The number of objects that are evaluated by the current node during this timestep. This value is often different from SNOBJ, as many nodes do not process all the objects in a simulation.

NOBJ may return 0 if the node does not process each object sequentially (such as the Group DOP).

OBJ

The index of the specific object being processed by the node. This value always runs from zero to NOBJ-1 in a given timestep. It does not identify the current object within the simulation like OBJID or OBJNAME; it only identifies the object’s position in the current order of processing.

This value is useful for generating a random number for each object, or simply splitting the objects into two or more groups to be processed in different ways. This value is -1 if the node does not process objects sequentially (such as the Group DOP).

OBJID

The unique identifier for the object being processed. Every object is assigned an integer value that is unique among all objects in the simulation for all time. Even if an object is deleted, its identifier is never reused. This is very useful in situations where each object needs to be treated differently, for example, to produce a unique random number for each object.

This value is also the best way to look up information on an object using the dopfield expression function.

OBJID is -1 if the node does not process objects sequentially (such as the Group DOP).

ALLOBJIDS

This string contains a space-separated list of the unique object identifiers for every object being processed by the current node.

ALLOBJNAMES

This string contains a space-separated list of the names of every object being processed by the current node.

OBJCT

The simulation time (see variable ST) at which the current object was created.

To check if an object was created on the current timestep, the expression $ST == $OBJCT should always be used.

This value is zero if the node does not process objects sequentially (such as the Group DOP).

OBJCF

The simulation frame (see variable SF) at which the current object was created. It is equivalent to using the dopsttoframe expression on the OBJCT variable.

This value is zero if the node does not process objects sequentially (such as the Group DOP).

OBJNAME

A string value containing the name of the object being processed.

Object names are not guaranteed to be unique within a simulation. However, if you name your objects carefully so that they are unique, the object name can be a much easier way to identify an object than the unique object identifier, OBJID.

The object name can also be used to treat a number of similar objects (with the same name) as a virtual group. If there are 20 objects named “myobject”, specifying strcmp($OBJNAME, "myobject") == 0 in the activation field of a DOP will cause that DOP to operate on only those 20 objects.

This value is the empty string if the node does not process objects sequentially (such as the Group DOP).

DOPNET

A string value containing the full path of the current DOP network. This value is most useful in DOP subnet digital assets where you want to know the path to the DOP network that contains the node.

Note

Most dynamics nodes have local variables with the same names as the node’s parameters. For example, in a Position DOP, you could write the expression:

$tx + 0.1

…to make the object move 0.1 units along the X axis at each timestep.

Examples ¶

DampedHinge Example for RBD Angular Spring Constraint dynamics node

This example shows how to use the RBD Angular Spring Constraint to create a damped hinge.

SimpleRotationalConstraint Example for RBD Angular Spring Constraint dynamics node

This example demonstrates the use of an RBD Angular Spring Constraint.

Dynamics nodes

Active Value

Marks a simulation object as active or passive.
Affector

Creates affector relationships between groups of objects.
Agent Arcing Clip Layer

Blends between a set of animation clips based on the agent’s turn rate.
Agent Clip Layer

Layers additional animation clips onto an agent.
Agent Look At

Defines a target that an agent can turn its head to look at.
Agent Look At Apply

Adjusts the agent’s skeleton to look at a target.
Agent Terrain Adaptation

Adapts the legs of an agent to conform to terrain and prevent the feet from sliding.
Agent Terrain Projection

Project the agent/particle points onto the terrain
Anchor: Align Axis

Defines an orientation that aligns an axis in object space with a second axis defined by the relative locations of two positional anchors.
Anchor: Object Point Group Position

Defines multiple points, specified by their number or group, on the given geometry of a simulation object.
Anchor: Object Point Group Rotation

Defines orientations based on multiple points on the given geometry of a simulation object.
Anchor: Object Point Id Position

Defines a position by looking at the position of a point on the geometry of a simulation object.
Anchor: Object Point Id Rotation

Defines an orientation by looking at a point on the geometry of a simulation object.
Anchor: Object Point Number Position

Defines a position by looking at the position of a point on the geometry of a simulation object.
Anchor: Object Point Number Rotation

Defines an orientation by looking at a point on the geometry of a simulation object.
Anchor: Object Primitive Position

Defines a position by looking at the position of a particular UV coordinate location on a primitive.
Anchor: Object Space Position

Defines a position by specifying a position in the space of some simulation object.
Anchor: Object Space Rotation

Defines an orientation by specifying a rotation in the space of some simulation object.
Anchor: Object Surface Position

Defines multiple attachment points on a polygonal surface of an object.
Anchor: World Space Position

Defines a position by specifying a position in world space.
Anchor: World Space Rotation

Defines an orientation by specifying a rotation in world space.
Apply Data

Attaches data to simulation objects or other data.
Apply Relationship

Creates relationships between simulation objects.
Blend Factor
Blend Solver
Bullet Data

Attaches the appropriate data for Bullet Objects to an object.
Bullet Soft Constraint Relationship
Bullet Solver

Sets and configures a Bullet Dynamics solver.
Buoyancy Force

Applies a uniform force to objects submerged in a fluid.
Cloth Configure Object

Attaches the appropriate data for Cloth Objects to an object.
Cloth Mass Properties

Defines the mass properties.
Cloth Material

Defines the physical material for a deformable surface.
Cloth Material Behavior

Defines the internal cloth forces.
Cloth Object

Creates a Cloth Object from SOP Geometry.
Cloth Plasticity Properties

Defines the plasticity properties.
Cloth Solver
Cloth Solver
Cloth Solver
Cloth Stitch Constraint

Constrains part of the boundary of a cloth object to the boundary of another cloth object.
Cloth Target Properties

Defines how cloth uses target.
Cloth Visualization
Cloth/Volume Collider

Defines a way of resolving collisions involving a cloth object and DOPs objects with volumetric representations (RBD Objects, ground planes, etc.)
Collide Relationship
Collider Label
Cone Twist Constraint

Constrains an object to remain a certain distance from the constraint, and limits the object’s rotation.
Cone Twist Constraint Relationship
Constraint
Constraint Network

Constrains pairs of RBD objects together according to a polygon network.
Constraint Network Relationship

Defines a set of constraints based on geometry.
Constraint Network Visualization

Visualizes the constraints defined by constraint network geometry.
Constraint Relationship
Container
Copy Data

Creates multiple copies of the input data.
Copy Data Solver

Sets and configures a Copy Data Solver.
Copy Object Information

Mimics the information set by the Copy Object DOP.
Copy Objects
Crowd Fuzzy Logic

Defines a Crowd Fuzzy Logic
Crowd Object

Creates a crowd object with required agent attributes to be used in the crowd simulation.
Crowd Solver

Updates agents according to their steer forces and animation clips.
Crowd State

Defines a Crowd State
Crowd Transition

Defines a transition between crowd states.
Crowd Trigger

Defines a Crowd Trigger
Crowd Trigger Logic

Combines multiple crowd triggers to build a more complex trigger.
Data Only Once

Adds a data only once to an object, regardless of number of wires.
Delete

Deletes both objects and data according to patterns.
Drag Force

Applies force and torque to objects that resists their current direction of motion.
Drag Properties

Defines how the surrounding medium affects a soft body object.
Embedding Properties

Controls Embedded Geometry that can be deformed along with the simulated geometry in a finite element simulation.
Empty Data

Creates an Empty Data for holding custom information.
Empty Object

Creates an Empty Object.
Empty Relationship
Enable Solver
FEM Attach Constraint

Constrains a set of points on the surface of one FEM object to a set of points on the surface on another FEM object or a static object.
FEM Fuse Constraint

Constrains points of a solid object or a hybrid object to points of another DOP object.
FEM Hybrid Object

Creates an FEM Hybrid Object from SOP Geometry.
FEM Region Constraint

Constrains regions of a solid object or a hybrid object to another solid or hybrid object.
FEM Slide Constraint

Make a set of points on the surface of an FEM Object slide against the surface of another FEM Object or a Static Object.
FEM Solid Object

Creates a simulated FEM solid from geometry.
FEM Solver
FEM Solver

Sets and configures a Finite Element solver.
FEM Target Constraint

Constrains an FEM object to a target trajectory using a hard constraint or soft constraint.
FLIP Configure Object

Attaches the appropriate data for Particle Fluid Objects to become a FLIP based fluid.
FLIP Solver

Evolves an object as a FLIP fluid object.
FLIP fluid object
Fan Force

Applies forces on the objects as if a cone-shaped fan were acting on them.
Fetch Data

Fetches a piece of data from a simulation object.
Field Force

Applies forces to an object using some piece of geometry as a vector field.
Filament Object

Creates a vortex filament object from SOP Geometry.
Filament Solver

Evolves vortex filament geometry over time.
Filament Source

Imports vortex filaments from a SOP network.
File

Saves and loads simulation objects to external files.
File Data
Finite Element Output Attributes

Allows a finite-element object to generate optional output attributes.
Fluid Configure Object

Attaches the appropriate data for Fluid Objects to an object.
Fluid Force

Applies forces to resist the current motion of soft body objects relative to a fluid.
Fluid Object

Attaches the appropriate data for Fluid Objects to an object.
Fluid Solver

A solver for Sign Distance Field (SDF) liquid simulations.
Gas Adaptive Viscosity

A microsolver that applies viscosity to a velocity field using an adaptive grid.
Gas Advect

A microsolver that advects fields and geometry by a velocity field.
Gas Advect CL

A microsolver that advects fields by a velocity field using OpenCL acceleration.
Gas Advect Field

A microsolver that advects fields by a velocity field.
Gas Analysis

A microsolver that computes analytic property of fields.
Gas Attribute Swap

A microsolver that swaps geometry attributes.
Gas Axis Force

A microsolver that applies a force around an axis to a velocity field.
Gas Blend Density

A microsolver that blends the density of two fields.
Gas Blur

A microsolver that blurs fields.
Gas Build Collision Mask

A microsolver that determines the collision field between the fluid field and any affector objects.
Gas Build Collision Mask From Pieces

A microsolver that builds a collision field for fluid simulations from instanced pieces.
Gas Build Occupancy Mask

A microsolver that builds a mask out of positive areas of the source fields.
Gas Build Relationship Mask

A microsolver that builds a mask for each voxel to show the presence or absence of relationships between objects.
Gas Buoyancy

A microsolver that calculates an adhoc buoyancy force and updates a velocity field.
Gas Calculate

A microsolver that performs general calculations on a pair of fields.
Gas Collision Detect

A microsolver that detects collisions between particles and geometry.
Gas Combustion

A microsolver that applies a combustion model to the simulation.
Gas Convex Clip SDF

A microsolver that clips an SDF field with a convex hull.
Gas Correct By Markers

A microsolver that adjusts an SDF according to surface markers.
Gas Cross

A microsolver that computes the cross product of two vector fields.
Gas Curve Force

A DOP node that creates forces generated from a curve.
Gas Damp

A microsolver that scales down velocity, damping motion.
Gas Diffuse

A microsolver that diffuses a field or point attribute.
Gas Dissipate

A microsolver that dissipates a field.
Gas Disturb

Adds fine detail to a smoke simulation by applying disturbance forces to a velocity field.
Gas Each Data Solver

A microsolver that runs once for each matching data.
Gas Embed Fluid

A microsolver that embeds one fluid inside another.
Gas Enforce Boundary

A microsolver that enforces boundary conditions on a field.
Gas Equalize Density

A microsolver that equalizes the density of two fields.
Gas Equalize Volume

A microsolver that equalizes the volume of two fields.
Gas Error

A microsolver that emits a DOP error.
Gas External Forces

A microsolver that evaluates the external DOPs forces for each point in a velocity field and updates the velocity field accordingly.
Gas Extrapolate

A microsolver that extrapolates a field’s value along an SDF.
Gas Feather Field

A microsolver that creates a feathered mask out of a field.
Gas Feedback

A microsolver that calculates and applies feedback forces to collision geometry.
Gas Fetch Fields to Embed

A data node that fetches the fields needed to embed one fluid in another.
Gas Field VOP

Runs CVEX on a set of fields.
Gas Field Wrangle

Runs CVEX on a set of fields.
Gas Field to Particle

A microsolver that copies the values of a field into a point attribute on geometry.
Gas Filter Hourglass Modes

Filters spurious divergent modes that may survive pressure projection on a center-sampled velocity field.
Gas Geometry Defragment

A microsolver that defragments geometry.
Gas Geometry to SDF

A microsolver that creates a signed distance field out of geometry.
Gas Geometry/Option Transfer

A micro solver that transfers meta data on simulation objects to and from geometry attributes.
Gas Guiding Volume

Blends a set of SOP volumes into a set of new collision fields for the creation of a guided simulation.
Gas Impact to Attributes

A microsolver that copies Impact data onto point attributes.
Gas Integrate Shallow Water Equations

Integrates the shallow water equations.
Gas Integrator

A microsolver that applies forces to a particle fluid system.
Gas Interleave Solver

A microsolver that repeatedly solves its inputs at different rates.
Gas Intermittent Solve

A microsolver that solves its subsolvers at a regular interval.
Gas Limit

A microsolver that clamps a field within certain values.
Gas Limit Particles

A microsolver that keeps particles within a box.
Gas Linear Combination

A microsolver that combines multiple fields or attributes together.
Gas Local Sharpen

A microsolver that adaptively sharpens a field.
Gas Lookup

A microsolver that looksup field values according to a position field.
Gas Match Field

A microsolver that rebuilds fields to match in size and resolution to a reference field.
Gas Net Fetch Data

A microsolver that arbitrary simulation data between multiple machines.
Gas Net Field Border Exchange

A microsolver that exchanges boundary data between multiple machines.
Gas Net Field Slice Exchange

A microsolver that exchanges boundary data between multiple machines.
Gas Net Slice Balance

A microsolver that balances slices data between multiple machines.
Gas Net Slice Exchange

A microsolver that exchanges boundary data between multiple machines.
Gas OpenCL

Executes the provided kernel with the given parameters.
Gas OpenCL Enforce Boundary

Uses OpenCL to perform boundary enforcement for fluid fields.
Gas OpenCL Merge VDB

Uses OpenCL to import VDB data from source geometry into simulation fields.
Gas Particle Count

A microsolver that counts the number of particles in each voxel of a field.
Gas Particle Move to Iso

A microsolver that moves particles to lie along a certain isosurface of an SDF.
Gas Particle Separate

A microsolver that separates adjacent particles by adjusting their point positions..
Gas Particle to Field

A microsolver that copies a particle system’s point attribute into a field.
Gas Particle to SDF

A microsolver that converts a particle system into a signed distance field.
Gas Project Non Divergent

A microsolver that removes the divergent components of a velocity field.
Gas Project Non Divergent Adaptive

A microsolver that removes the divergent components of a velocity field using an adaptive background grid to increase performance.
Gas Project Non Divergent Multigrid

A microsolver that removes the divergent components of a velocity field using a multi-grid method.
Gas Project Non Divergent Variational

A microsolver that removes the divergent components of a velocity field.
Gas Reduce

A microsolver that reduces a field to a single constant field .
Gas Reduce Local

A microsolver that reduces surrounding voxels to a single value.
Gas Reinitialize SDF

A microsolver that reinitializes a signed distance field while preserving the zero isocontour.
Gas Repeat Solver

A microsolver that repeatedly solves its input.
Gas Reset Inactive

A microsolver that resets fields outside of the stenciled region.
Gas Resize Field

A microsolver that changes the size of fields.
Gas Resize Fluid Dynamic

A microsolver that resizes a fluid to match simulating fluid bounds
Gas Rest

A microsolver that initializes a rest field.
Gas SDF to Fog

A microsolver that converts an SDF field to a Fog field.
Gas Sand Forces

A microsolver that computes the forces to treat the fluid simulation as sand rather than fluid.
Gas Seed Fluid Particles

A microsolver that creates, deletes and reseeds particles. Tailored to be used in a fluid solver.
Gas Seed Markers

A microsolver that seeds marker particles around the boundary of a surface.
Gas Seed Particles

A microsolver that seeds particles uniformly inside a surface.
Gas Shred

Applies a Shredding Force to the velocity field specified.
Gas Slice To Index Field

A microsolver that computes slice numbers into an index field.
Gas Stick on Collision

Adjusts a fluid velocity field to match collision velocities.
Gas Strain Forces

A microsolver that calculates the forces imparted by a strain field.
Gas Strain Integrate

A microsolver that updates the strain field according to the current velocity field.
Gas SubStep

A microsolver that substeps input microsolvers.
Gas Surface Snap

A microsolver that snaps a surface onto a collision surface.
Gas Surface Tension

A microsolver that calculates a surface tension force proportional to the curvature of the surface field.
Gas Synchronize Fields

A microsolver that synchronizes transforms of simulation fields.
Gas Target Force

A microsolver that applies a force towards a target object.
Gas Temperature Update

Modifies the temperature of a FLIP over time.
Gas Turbulence

Applies Turbulence to the specified velocity field.
Gas Up Res

Up-scales and/or modifies a smoke, fire, or liquid simulations.
Gas Velocity Scale

Scales fluid velocity based on the fluid’s current speed or a control field.
Gas Velocity Stretch

A microsolver that reorients geometry according to motion of a velocity field.
Gas Viscosity

A microsolver that applies viscosity to a velocity field.
Gas Volume

A microsolver that seeds flip particles into a new volume region.
Gas Volume Ramp

Remaps a field according to a ramp.
Gas Vortex Boost

Applies a confinement force on specific bands of sampled energy.
Gas Vortex Confinement

Applies a vortex confinement force to a velocity field.
Gas Vortex Equalizer

Applies a confinement force on specific bands of sampled energy.
Gas Vorticle Forces

A microsolver that applies forces to a velocity field or geometry according to vorticle geometry.
Gas Vorticle Geometry

A DOP node that adds the appropriately formatted data to represent vorticles.
Gas Vorticle Recycle

A DOP node that recycles vorticles by moving them to the opposite side of the fluid box when they leave.
Gas Wavelets

A microsolver that performs a wavelet decomposition of a field.
Gas Wind

A microsolver that applies a wind force.
Geometry Copy
Geometry VOP

Runs CVEX on geometry attributes.
Geometry Wrangle

Runs a VEX snippet to modify attribute values.
Glue Constraint Relationship
Gravity Force

Applies a gravity-like force to objects.
Ground Plane

Creates a ground plane suitable for RBD or cloth simulations.
Group

Creates simulation object groups.
Group Relationship
Hard Constraint Relationship

Defines a constraint relationship that must always be satisfied.
Hybrid Configure Object

Attaches the appropriate data for Hybrid Objects to an object.
Impact Analysis

Stores filtered information about impacts on an RBD object. The shelf tool has no effect in the viewport, it just sets up nodes in the network to record the impact data.
Impulse Force

Applies an impulse to an object.
Index Field

Creates an index field.
Index Field Visualization

Visualizes an index field.
Instanced Object

Creates DOP Objects according to instance attributes
Intangible Value

Marks a simulation object as intangible or tangible.
Link to Source Object

Stores the name of the scene level object source for this DOP object.
Magnet Force

Apply forces on objects using a force field defined by metaballs.
Mask Field
Matrix Field

Creates a matrix field.
Matrix Field Visualization

Visualizes a matrix field.
Merge

Merges multiple streams of objects or data into a single stream.
Modify Data

Modifies or creates options on arbitrary data.
Motion

Defines an object’s position, orientation, linear velocity, and angular velocity.
Multi Field Visualization

Unified visualization of multiple fields.
Multiple Solver
Net Fetch Data

A DOP that transfers arbitrary simulation data between multiple machines.
No Collider
No Constraint Relationship
Noise Field
Null

Does nothing.
OBJ Position

Creates position information from an object’s transform.
POP Advect by Filaments

Uses vortex filaments to move particles.
POP Advect by Volumes

A POP node that uses velocity volumes to move particles.
POP Attract

A POP node that attracts particles to positions and geometry.
POP Attribute Blur

The POP equivalent of the Attribute Blur SOP.
POP Attribute from Volume

A POP node that copies volume values into a particle attribute.
POP Awaken

A POP node that resets the stopped attribute on particles, waking them up.
POP Axis Force

A POP node that applies a force around an axis.
POP Collision Behavior

A POP node that reacts to collisions.
POP Collision Detect

A POP node that detects and reacts to collisions.
POP Collision Ignore

A POP node marks particles to ignore implicit collisions.
POP Color

A POP node that colors particles.
POP Curve Force

A POP node that creates forces generated from a curve.
POP Curve Incompressible Flow

A POP node that creates incompressible velocity field generated from a curve.
POP Drag

A POP node that applies drag to particles.
POP Drag Spin

A POP node that applies drag to the spin of particles.
POP Fan Cone

A POP node that applies a conical fan wind to particles.
POP Fireworks

A POP node that creates a simple fireworks system.
POP Float by Volumes

A POP node that floats particles on the surface of a liquid simulation.
POP Flock

A POP node that applies a flocking algorithm to particles.
POP Fluid

Controls local density by applying forces between nearby particles.
POP Force

A POP node that applies forces to particles.
POP Grains

A POP node that applies sand grain interaction to particles.
POP Group

A POP node that groups particles.
POP Hair Internal Force

Compute hair separation force using a VDB volume approach.
POP Instance

A POP node that sets up the instancepath for particles.
POP Interact

A POP node that applies forces between particles.
POP Kill

A POP node that kills particles.
POP Limit

A POP node that limits particles.
POP Local Force

A POP node that applies forces within the particle’s frame.
POP Location

A POP solver that generates particles at a point.
POP Lookat

A POP node makes a particle look at a point.
POP Mask from Shadow

A POP node that creates a mask based on whether particles are occluded by geometry.
POP Metaball Force

A POP node that applies forces according to metaballs.
POP Object

Converts a regular particle system into a dynamic object capable of interacting correctly with other objects in the DOP environment.
POP Properties

A POP node that sets various common attributes on particles.
POP Proximity

A POP node that sets attributes based on nearby particles.
POP Replicate

A POP Node that generates particles from incoming particles.
POP Soft Limit

A POP node that creates a spongy boundary.
POP Solver

A POP solver updates particles according to their velocities and forces.
POP Source

A POP node that generates particles from geometry.
POP Speed Limit

A POP node that sets the speed limits for particles.
POP Spin

A POP node that sets the spin of particles..
POP Spin by Volumes

A POP node that uses the vorticity of velocity volumes to spin particles.
POP Sprite

A POP node that sets the sprite display for particles.
POP Steer Align

Applies force to agents/particles to align them with neighbors.
POP Steer Avoid

Applies anticipatory avoidance force to agents/particles to avoid potential future collisions with other agents/particles.
POP Steer Cohesion

Applies forces to agents/particles to bring them closer to their neighbors.
POP Steer Custom

Applies forces to agents/particles calulated using a VOP network.
POP Steer Obstacle

Applies force to agents/particles to avoid potential collisions with static objects.
POP Steer Path

Applies force to agents/particles according to directions from a path curve.
POP Steer Seek

Applies force to agents/particles to move them toward a target position.
POP Steer Separate

Apply force to agents/particles to move them apart from each other.
POP Steer Solver

Used internally in the crowd solver to integrate steering forces.
POP Steer Turn Constraint

Constrains agent velocity to only go in a direction within a certain angle range of its current heading, to prevent agents from floating backward.
POP Steer Wander

Apply forces to agents/particles to create a random motion.
POP Stream

A POP node that creates a new stream of particles.
POP Torque

A POP node that applies torque to particles, causing them to spin.
POP VOP

Runs CVEX on a particle system.
POP Velocity

A POP node that directly changes the velocity of particles.
POP Wind

A POP node that applies wind to particles.
POP Wind Shadow

Applies a wind shadow to particles
POP Wrangle

Runs a VEX snippet to modify particles.
Particle Fluid Density CL

Solves a Smoothed Particle Hydrodynamics (SPH) density constraint for fluid particles using OpenCL.
Particle Fluid Forces CL

A microsolver for particle fluid forces
Particle Fluid Visualization

Visualizes particles.
Partition

Creates simulation object groups based on an expression.
Physical Parameters

Defines the base physical parameters of DOP objects.
Point Collider
Point Force

Applies a force to an object from a particular location in space.
Point Position

Creates position information from a point on some SOP geometry.
Position

Associates a position and orientation to an object.
Pump Relationship
Pyro Solver

Sets and configures a Pyro solver. This solver can be used to create both fire and smoke.
Pyro Solver (Sparse)

Performs a sparse pyro simulation on the given object. This solver can be used to create both fire and smoke.
RBD Angular Constraint

Constrains an RBD object to a certain orientation.
RBD Angular Spring Constraint

Constrains an RBD object to have a certain orientation, but with a set amount of springiness.
RBD Auto Freeze

Automatically freezes RBD Objects that have come to rest
RBD Car Follow Path

Constrain a RBD Car Rig along a path.
RBD Configure Object

Attaches the appropriate data for RBD Objects to an object.
RBD Fractured Object

Creates a number of RBD Objects from SOP Geometry. These individual RBD Objects are created from the geometry name attributes.
RBD Guide

Guide Bullet Packed Primitives.
RBD Hinge Constraint

Constrains an object to two constraints, creating a rotation similar to a hinge or a trapeze bar.
RBD Keyframe Active
RBD Object

Creates an RBD Object from SOP Geometry.
RBD Packed Object

Creates a single DOP object from SOP Geometry that represents a number of RBD Objects.
RBD Pin Constraint

Constrains an RBD object a certain distance from the constraint.
RBD Point Object

Creates a simulation object at each point of some source geometry, similarly to how the Copy surface node copies geometry onto points.
RBD Solver

Sets and configures a Rigid Body Dynamics solver.
RBD Spring Constraint

Constrains an object to remain a certain distance from the constraint, with a set amount of springiness.
RBD State

Alters the state information for an RBD Object.
RBD Visualization
ROP Output

Serves as the end-point of the simulation network. Has controls for writing out sim files.
ROP Output Driver

Saves the state of a DOP network simulation into files.
ROP Output Driver

Saves the state of a DOP network simulation into files.
Reference Frame Force

Applies forces to an object according to the difference between two reference frames.
Rendering Parameters Volatile
Rigid Body Solver

Sets and configures a Rigid Body Dynamics solver.
Ripple Configure Object

Attaches the appropriate data for Ripple Objects to an object.
Ripple Object

Creates an object from existing geometry that will be deformed with the ripple solver.
Ripple Solver

Animates wave propagation across Ripple Objects.
SDF Representation

Creates a signed distance field representation of a piece of geometry that can be used for collision detection.
SOP Geometry
SOP Guide
SOP Merge Field

A microsolver that performs general calculations on a pair consisting of a DOP field and a SOP volume/VDB.
SOP Scalar Field

Creates a scalar field from a SOP Volume.
SOP Solver
SOP Vector Field

Creates a vector field from a SOP Volume Primitive.
Scalar Field

Creates a scalar field.
Scalar Field Visualization

Visualizes a scalar field.
Script Solver
Seam Properties

Defines the internal seam angle.
Shell Mass Properties

Defines the mass density of a Cloth Object.
Sink Relationship
Slice Along Line

Divides a particle system uniformly into multiple slices along a line.
Slice by Plane

Specifies a cutting plane to divide a particle system into two slices for distributed simulations.
Slider Constraint

Constrains an object to rotate and translate on a single axis, and limits the rotation and translation on that axis.
Slider Constraint Relationship
Smoke Configure Object

Attaches the appropriate data for Smoke Objects to an object.
Smoke Object

Creates an Smoke Object from SOP Geometry.
Smoke Object (Sparse)

Creates an empty smoke object for a pyro simulation.
Smoke Solver

Sets and configures a Smoke solver. This is a slightly lower-level solver that is the basis for the Pyro solver.
Smoke Solver (Sparse)

Performs a sparse smoke simulation on the given object. This is a slightly lower-level solver that is the basis for the sparse pyro solver.
Soft Attach Constraint Relationship
Soft Body (SBD) Constraint

Constrains a set of points on a soft body object to a certain position using a hard constraint or soft constraint.
Soft Body (SBD) Pin Constraint

Constrains a point on a soft body object to a certain position.
Soft Body (SBD) Spring Constraint

Constrains a point on a soft body to a certain position, with a set amount of springiness.
Soft Body Collision Properties

Defines how a soft body object responds to collisions.
Soft Body Fracture Properties

Defines how a Soft Body Object responds to collisions.
Soft Body Fracture Properties

Defines how a Soft Body Object responds to collisions.
Soft Body Material Properties

Defines how a Soft Body Object responds to collisions.
Soft Body Rest Properties

Allows the user to import the rest state from a SOP node.
Soft Body Solver

Sets and configures a Soft Body solver.
Soft Body Target Properties

Defines the strengths of the soft constraint on a soft body object.
Solid Aniso Multiplier

Controls the anisotropic behavior of a Solid Object.
Solid Configure Object

Attaches the appropriate data for Solid Objects to an object.
Solid Mass Properties

Defines the mass density of a Solid Object.
Solid Model Data

Defines how a Solid Object reacts to strain and change of volume.
Solid Solver
Solid Solver
Solid Visualization
Source Relationship
Sphere Edge Tree

This builds a tree of spheres producing bounding information for an edge cloud.
Sphere Point Tree

This builds a tree of spheres producing bounding information for a point cloud.
Split Object

Splits an incoming object stream into as many as four output streams.
Spring Constraint Relationship
Static Object

Creates a Static Object from SOP Geometry.
Static Solver
Static Visualization

Allows you to inspect the behavior of a static object in the viewport.
Subnetwork
Surface Collision Parameters

Control the thickness of the object that collides with cloth.
Switch

Passes one of the input object or data streams to the output.
Switch Solver
Switch Value
Target Relationship
Terrain Object

Creates a Terrain Object from SOP Geometry.
Thin Plate/Thin Plate Collider

Defines a way of resolving collisions between two rigid bodies.
Two State Constraint Relationship
Uniform Force

Applies a uniform force and torque to objects.
VOP Force

Applies forces on the objects according to a VOP network.
Vector Field

Creates a vector field.
Vector Field Visualization

Visualizes a vector field.
Vellum Constraint Properties

Modifies common Vellum constraint properties during a Vellum solve.
Vellum Constraints

Microsolver to create Vellum constraints during a simulation.
Vellum Object

Creates a DOP Object for use with the Vellum Solver.
Vellum Rest Blend

Blends the current rest values of constraints with a rest state calculated from the current simulation or external geometry.
Vellum Solver

Sets and configures a Vellum solver.
Vellum Source

A Vellum node that creates Vellum patches.
Velocity Impulse Force

Applies an impulse to an object.
Visualize Geometry

A microsolver to create soft references to visualizers on itself.
Volume Instance Source

Uses instance points to source packed source sets into DOP fields.
Volume Source

Imports SOP source geometry into smoke, pyro, and FLIP simulations.
Volume/Volume Collider

Defines a way of resolving collisions involving two rigid bodies with volume.
Voronoi Fracture Configure Object

Attaches the appropriate data to make an object fractureable by the Voronoi Fracture Solver
Voronoi Fracture Parameters

Defines the parameters for dynamic fracturing using the Voronoi Fracture Solver
Voronoi Fracture Solver

Dynamically fractures objects based on data from the Voronoi Fracture Configure Object DOP
Vortex Force

Applies a vortex-like force on objects, causing them to orbit about an axis along a circular path.
Whitewater Object

Creates a Whitewater Object that holds data for a whitewater simulation.
Whitewater Solver

Sets and configures a Whitewater Solver.
Wind Force

Applies forces to resist the current motion of objects relative to a turbulent wind.
Wire Angular Constraint

Constrains a wire point’s orientation to a certain direction.
Wire Angular Spring Constraint

Constrains a wire point’s orientation to a certain direction, with a set amount of springiness.
Wire Configure Object

Attaches the appropriate data for Wire Objects to an object.
Wire Elasticity

Defines the elasticity of a wire object.
Wire Glue Constraint

Constraints a wire point to a certain position and direction.
Wire Object

Creates a Wire Object from SOP Geometry.
Wire Physical Parameters

Defines the physical parameters of a wire object.
Wire Plasticity

Defines the plasticity of a wire object.
Wire Solver

Sets and configures a Wire solver.
Wire Visualization
Wire/Volume Collider

Defines a way of resolving collisions involving a wire object and DOPs objects with volumetric representations.
Wire/Wire Collider

Defines a way of resolving collisions between two wires.
clothgeometry
standard_clothobjectattribs
standard_embedding_parms
standard_feoutputattributes_parms
standard_solidobjectattribs